Thread: Porting from db2 problem
Hi,I am trying to port an app that currently runs over db2 and oracle (on windows os/2 linux hpux aix etc) to also run over postgres.I am currently porting the windows client (using odbc). I am having majorproblems because of the lack of with hold cursors (cursors that remain open over a commit) in postgres. There are a lot of places where the app will - open a cursor with hold - fetch the first 20 or so rows, allow the user to scroll thru the result set, updating and commiting changes to particular rows as they go. When the user gets to the end of the current set of fetched rows - the app will fetch the next 20 or so during a scroll down operation etc. The user may hold the read-only cursor over the result-set all day, and it is important that rows that they do update, be immediately available for other users. What do folk do to support this kind of scenario in the abscence of with hold cursors ? Is implementation of with hold cursors likely in the near future? Regards, Wayne
> > I am trying to port an app that currently runs over db2 and oracle (on windows > os/2 linux hpux aix etc) to also run over postgres. > I am currently porting the windows client (using odbc). > I am having major problems because of the lack of with hold cursors (cursors > that remain open over a commit) in postgres. There are a lot of places where > the app will - open a cursor with hold - fetch the first 20 or so rows, allow > the user to scroll thru the result set, updating and commiting changes to > particular rows as they go. When the user gets to the end of the current set of > fetched rows - the app will fetch the next 20 or so during a scroll down > operation etc. The user may hold the read-only cursor over the result-set all > day, and it is important that rows that they do update, be immediately > available for other users. > > What do folk do to support this kind of scenario in the abscence of with hold > cursors ? Have a look at SELECT ... FOR UPDATE ... LIMIT ... OFFSET ... ; > Is implementation of with hold cursors likely in the near future? > I have no idea. Sorry. Regards, Christoph